I am relatively young, tall and strong. I don't find it all that bad doing it the brute force and ignorance method, by this I mean putting the pin in the step link and lifting the mast and having my wife put the forestay pin in. This method is also pretty quick. However I don't really like standing on the tramp with the boat on the trailer holding the mast.

Is it bad for the trampoline ? Has anyone ever fallen through ? I would imagine it could be pretty ugly. Does it put any bad loads on the boat ?

Should I look into some kind of winch and gin pole deal mainly for the sake of the tramp or have people been doing it that way for so long that it's generally fine and I can stop worrying.

Generally speaking, no issues with the tramp. The way you're doing it is the way its been done for the past 40 years. Only recommendation, if you can think of it, when you first step back to raise the mast, place your back foot on the rear crossbar rather than on the aft tramp lacings. This will help to reduce some of the stress on the rear grommets and prevent them pulling out. But as a general rule, standing on the tramp is fine and will not hurt it unless it is so worn that it needs to be replaced anyway.

As far as overloading the hulls, its also unlikely unless you're particularly heavy. Again, the way you're raising the mast is the way its been done by thousands of sailors for decades.